The invention relates to the retrieval of a wire line mass from a well bore, and especially to a tool and method for retrieving the wire line mass.
Downhole operations in oil and gas well bores are performed by equipment which is frequently run into the well bore by wire lines. Wire lines sometimes break or become separated and must be retrieved from the well bore. Unfortunately, the retrieval tools commonly used to engage or grab wire lines, such as barbed bodies, and shoe and washpipe tools, for example, are often unsuccessful and do no more than compress the wire line into a compacted mass, e.g., a so-called bird nest, which is even more difficult to retrieve. Among the most difficult wire lines to retrieve are insulated wire lines such as logging cables and electric wire lines of submergible pumps. Even if the prior retreival tools are successful, it often takes several attempts which is time-consuming, or may only retrieve small bits of the wireline in each attempt. Often, the operator will resort to the use of tungsten-carbide cutting tools to mill the bird nest out of the well bore. That is a costly and time-consuming operation.
It is, therefore, an object of the present invention to minimize or obviate problems of the type discussed above.
Another object of the invention is to provide methods and apparatus for more easily and reliably retrieving a wire line mass from a well bore, especially insulated wire lines.